Rich Dauer drove in five runs with two home runs, his second and third of the season, and Eddie Murray had four hits in five at bats, including his 14th homer, while driving in three more as the Baltimore Orioles defeated the Seattle Mariners tonight, 12-8.

Dauer had never hit two home runs in one game. Murray has 16 RBI in his last seven games.

The Orioles wasted little time in knocking out Seattle starter Jerry Don Gleaton, driving him from the game after only 2 2/3 innings on home runs by Ken Singleton and Dauer.

Singleton hit his 12th of the year with only one out in the first after Gleaton had walked Al Bumbry.

In the third, Bumbry drove a line drive deep to left and the ball skipped off the glove of Tom Paciorek for a two-base error. On the next pitch, Dauer homered for a 4-0 Baltimore lead.

Meanwhile, Dennis Martinez was nearly perfect through three innings. He did not permit a hit and allowed only one Seattle runner to reach base, Bruce Bochte on a walk in the first.

Baltimore threatened to turn it into a rout after Dauer's third-inning home run. With two out, Murray was safe on an infield single and Doug DeCinces singled to left, giving the Orioles runners at first and second.

At that point, Mariner Manager Rene Lachemann removed Gleaton in favor of Bob Galasso, and Galasso retired the side.

Galasso did not last long, however. The Orioles knocked him out with a five-run rally in their half of the fourth, which was highlighted by Dauer's second homer of the game, with two men on. Following singles by Rick Dempsey and Bumbry with two out, Dauer connected off Galasso, nearly putting the ball into the second deck of the Kingdome. That made it 7-0.

After Singleton and Murray got on base on a single and double, respectively, DeCinces hit a hard shot to Seattle third baseman Danny Meyer. Meyer threw wildly to first, allowing Singleton and Murray to score for a 9-0 lead.

Martinez, who had been supported by 10 hits through three innings while permitting none, faltered in the bottom of the fourth. After giving up successive singles to Bochte, Paciorek and Richie Zisk to load the bases, Martinez threw a hanging curve to Seattle right fielder Jeff Burroughs. Burroughs hit a grand slam, cutting Baltimore's lead to 9-4.

Baltimore scored two runs in the fifth for an 11-4 lead. After successive singles by Cal Ripken, Dempsey and Bumbry, Dauer hit into a double play before Murray drove in Ripken and Dempsey with a single, the Orioles' 14th hit of the game.

Martinez had no trouble with the Mariners in the fifth or sixth, allowing only a single to Zisk.

But in the seventh Martinez began to waver again. After Joe Simpson reached first on a throwing error and Julio Cruz had walked, Bochte hit a single to score Simpson. Paciorek then singled, sending Cruz home and cutting the Orioles' lead to 11-6.

At that point, Manager Earl Weaver decided Martinez had enough and lifted him in favor of Tim Stoddard. Stoddard promptly walked Zisk, loading the bases, and then walked Burroughs, forcing in a run. Stoddard escaped further trouble by getting Lenny Randle to fly to left, ending the inning.

Murray homered in the eighth to make it 12-7. Zisk homered in the ninth.